Doped lignin polymer

Abstract

A polymer that has been made of lignen and that contains sulphur, and into which a compound that activates the conductivity, such as iodine or ferric chloride, has been doped. The doped lignin polymer has properties of a semiconductor.

What is claimed is: 
     
       1. Doped lignin polymer comprising an undoped polymer containing a maximum of 55 percent by weight of sulphur and a compound activating the conductivity of said polymer in a quantity of 0.1 to 60 percent of the weight of the undoped polymer. 
     
     
       2. Lignin polymer as claimed in claim 1 wherein the compound that activates the conductivity is iodine, bromine, chlorine, iodine bromide, iodine chloride, arsenic pentafluoride, ferric chloride, molybdenum pentachloride, stannic chloride, sulphuric acid, or perchloric acid. 
     
     
       3. Lignin polymer as claimed in claim 2 wherein the compound that activates the conductivity is iodine. 
     
     
       4. Lignin polymer as claimed in claim 2 wherein the compound that activates the conductivity is ferric chloride. 
     
     
       5. Lignin polymer as claimed in claim 2 wherein the agent that activates the conductivity is arsenic pentafluoride. 
     
     
       6. Lignin polymer as claimed in claim 1 wherein the agent that activates the conductivity is lithium, sodium, or potassium. 
     
     
       7. Process for the preparation of a lignin polymer as claimed in claim 1 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       8. Process for the preparation of a lignin polymer as claimed in claim 1 comprising adding the compound activating the conductivity of said undoped polymer by means of a solution of the compound in an organic solvent. 
     
     
       9. Process as claimed in claim 7 wherein the activating agent is added in an inert atmosphere. 
     
     
       10. Process for the preparation of a lignin polymer as claimed in claim 2 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       11. Process for the preparation of a lignin polymer as claimed in claim 3 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       12. Process for the preparation of a lignin polymer as claimed in claim 4 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       13. Process for the preparation of a lignin polymer as claimed in claim 5 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       14. Process for the preparation of a lignin polymer as claimed in claim 6 comprising adding the compound activating the conductivity of said undoped polymer by means of vaporization. 
     
     
       15. Process for the preparation of a lignin polymer as claimed in claim 2 comprising adding the compound activating the conductivity of said undoped polymer by means of a solution of the compound in an organic solvent. 
     
     
       16. Process for the preparation of a lignin polymer as claimed in claim 3 comprising adding the compound activating the conductivity of said undoped polymer by means of a solution of a compound in an organic solvent. 
     
     
       17. Process as claimed in claim 8 wherein the activating agent is added in an inert atmosphere. 
     
     
       18. Doped lignin polymer comprising an undoped polymer containing a maximum of 55% by weight of sulfur and a p-type or n-type compound activating the conductivity of said polymer in a quantity of 0.1 to 60% of the weight of the undoped polymer.